41.2 Features
The following are key features of the GMAC:
- Compatible with IEEE Standard 802.3
- 10/100 Mbps operation
- Full and half duplex operation at all supported speeds of operation
- Statistics Counter Registers for RMON/MIB
- MII/RMII interface to the physical layer
- Integrated physical coding
- Direct memory access (DMA) interface to external memory
- Programmable burst length and endianism for DMA
- Interrupt generation to signal receive and transmit completion, errors or other events
- Automatic pad and cyclic redundancy check (CRC) generation on transmitted frames
- Automatic discard of frames received with errors
- Receive and transmit IP, TCP, and UDP checksum offload. Both IPv4 and IPv6 packet types supported
- Address checking logic for four specific 48-bit addresses, four type IDs, promiscuous mode, hash matching of unicast and multicast destination addresses, and Wake-on-LAN
- Management Data Input/Output (MDIO) interface for physical layer management
- Support for jumbo frames up to 10240 Bytes
- Full duplex flow control with recognition of incoming pause frames and hardware generation of transmitted pause frames
- Half duplex flow control by forcing collisions on incoming frames
- Support for 802.1Q VLAN tagging with recognition of incoming VLAN and priority tagged frames
- Programmable Inter Packet Gap (IPG) Stretch
- Recognition of IEEE 1588 PTP frames
- IEEE 1588 time stamp unit (TSU) and TSU event generation
- Support for 802.1AS timing and synchronization
- Supports 802.1Qav traffic shaping on two highest priority queues
- Support for 802.3az Energy Efficient Ethernet